It seems to me that there is something missing in the discussion of how much energy is represented by different foods. Please explain to me if this is incorrect, but from my own experience I would say that certain foods are easier to digest and break down than others. Therefore the net energy increase would be the total of calories ingested minus the energy needed for the digestive process. Eating easily digested food would be like feeding your plants manure tea: the nutritents are more available so the organism doesn't have to use up energy for assimilation and can therefore apply that energy to increased growth.

A heavy Thanksgiving type meal that leaves us bloated etc. takes a heavy toll on the body when digestion occurs. Isn't that why we get sleepy after a big meal? So if a person wanted quick energy, s/he might correctly choose a food which needs less breaking down: orange juice, or vegetables, or maybe even meat as opposed to pizza, potato casserole etc. All you fruitarians out there can back me up, or is this just another new age theory without scientific basis?

Also, isn't the idea of caloric content as measured by the doohickey machine when a chamber of ground pelleted food is burned by electrodes misleading. Is there a difference in the ability of foods to be broken down? Doesn't some of the food energy pass through the body unused. Chew your almonds everyone.